N.A.W. - Jupiter & Saturn

National Astronomy Week ran from 1st - 8th March and our meeting on Tuesday 4th slotted in well.
The focus for the week was Jupiter - beautifully positioned for viewing this month and happily, for once, we had a clear sky to enjoy it - more about that later.

A good turn-out, perhaps prompted by the clear skies - we counted (loosely) 37 in attendance.

1st on the agenda was the item - "What's Up in March" ably covered by Mike.
5 planets can be seen at different times of the night in March and the winter constellations are now beginning to give way to the Spring constellations of Leo and Virgo. Some interesting galaxies are to be found in these and later we managed to locate a few.

After a short break Kim treated us to his findings related to Jupiter.

Essentially it is a gas giant composed predominantly of hydrogen (90%) and helium (10%) though below its cloud layers there are the more exotic substances that live at high pressures - liquid hydrogen and solid hydrogen.

Because there is no solid ground, the surface of Jupiter is defined as the point where the atmospheric pressure is equal to that of Earth.  
At this point, the pull of gravity is almost two and a half times stronger than it is on our planet.

Trying to stand on that surface would be impossible, since it is simply another layer of gases.

A probe or spacecraft traveling  toward the center of the planet would continue to find only thick clouds until it reached the core.

The composition of the core is still a matter of debate but it's size is larger than the Earth as can be seen from the cut-away image above.

Just after 8.00p.m. we ventured out to a clear sky. I counted 7 telescopes plus  a few binoculars  so there was plenty to see.
One of the projects for N.A.W. was to count the number of naked eye stars visible in Orion - or more precisely the trapezium bounded by Betelgeuse, Bellatrix, Saiph and Rigel.
Some members excelled at this - Goodwick Mike counted 25, others (Liz and Brian were mentioned) saw a few more. I struggled to see 10!!
We would have quite a list if I were to detail all the sights seen that night - fortunately the Moon was just a crescent so didn't interfere and so we could see galaxies and open clusters that would otherwise be imposible.
I don't know if anyone saw the Great Red Spot on Jupiter but the 2 bands and moons were clearly seen.
It was a fitting conclusion to the night that we could actually see what we had been considering earlier - and it's not too often that that can be said!!